Maybe you've already read it, but I found terryb's guide helpful.

https://pinside.com/pinball/forum/topic/terrybs-guide-to-repairing-alkaline-battery-damage

Love the nail color by the way

I’d toss the battery holder. Too many nooks and crannies . Pull u22 in case and check. Looks pretty good otherwise. Maybe scrape around the battery board solder connections, maybe some bubbling there. Then Give it a shot.

Glad you got the new thread going. Until your board is solid all the other issues could be caused by it.

faz

All are 1/8 Watt. Resistor values can be found here:
https://pinside.com/pinball/forum/topic/wpc-89-cpu-board-info#post-3516478

Inspect traces in red circles, they look corroded as well. And possible under the socket of U20.
wpc89-1 (resized).jpg

If you mean the 4 resistors just above U20 (R35-R38), they are 10K. The colors are faded but used to be Black-Brown-Orange. With a multimeter you can measure the resistors. It will show close to 10.000 Ohm.

it is ok to use 1/4 Watt.
https://www.marcospecialties.com/pinball-parts/R025W10K

socket:
https://www.marcospecialties.com/pinball-parts/DIP18

edit:
make that Brown-Black-Orange

Your board has 21K resistors installed. These are simply pull up resistors on the open collector outputs from the quad comparators. 10K will work, 21K will work (but not a standard value), 22K should also work. But I would go down in value to standard value for that location - anything between 10K and 20K.

More than just the resistors and U20, it went under the U20 IC socket, which will be a bit difficult to remove. Also U16 was hit as well as the "B" capacitor. 2018-12-27 12_41_59-Help on assessing battery leakage board damage Bally WPC _ Tech_ Generic _ Pinsi (resized).png

Also you have an area I marked off where the dark areas are actually is the alkaline that got under the solder mask. Best to remove all the parts and then sand on the affected areas, then treating the areas then you can install the new parts. 2018-12-27 12_42_55- (resized).png

As long as there is any of this dull look to any of the parts, it is best to only apply heat to the backside of the board. If you put any heat on the top side of the affected area, the heat will speed up the damage quickly and just eat it up. Once you have the area sanded, it will not be any problem applying heat to the area.

Here you can see a before and after photo of a board I repaired.20170408_115512 (resized).jpg20170409_111916 (resized).jpg

https://pinside.com/pinball/forum/topic/stripping-battery-corrosion-with-a-strong-acid

You NEED to use stronger acid than vinegar, or the corrosion will return.

Read the above link and do it right.

send them to borygard or chris hibler they will get you fixed up. still a lot of damage there that will come back to haunt you.

A brand new, unpopulated PCB board is ~$40

I'm driving, but a bunch of online stores and ebay sells them

They both will add NVRAM to get rid of those batteries forever.

It definitely would be a bit cheaper having the original board repaired, which I prefer.

Well, you will need a PLCC tool to remove the U9 ASIC chip to move over along with the CPU chip and game ROM.

After you move the parts over, you can resell the old board.

Sell it to help fund machine #2 or stash it away to fix a game down the road.

I had this issue on my Medieval Madness when I bought it. It had battery corrosion when I bought it, only in the battery holder. I cleaned it with vinegar after getting the game and moved the batteries to a remote holder away from the boards. Two years later, after having the batteries in a remote holder, the corrosion spread from the battery holder causing the game all kinds of issues. Had to send the board out to Chris Hibler for repairs. Vid is correct, sometimes cleaning the board or battery holder with vinegar will not do the job. I saw Clay Harrell use yellow mustard on a board to kill the acid.

Mustard is only acidic because it has.....wait for it......vinegar in it.

So it's nowhere near strong enough to neutralize the alkali salts from a battery.

So damned important to replace/change those batteries once a year.. I use a remote holder as well. Someday I will stop being lazy and go NVRam on all my machines.

Or use Enloop rechargeable batteries, the game will keep them charged, and there is nothing in them to leak.

Camera guys swear by them.

battery-100812-2 (resized).jpg

I will have to check them out.

I'm probably in the minority here, but I say fix it yourself. You have a board on the way, if you mess it up, no big deal. It's not a rare board, you don't have much to lose. Someone may pay $50 for the damaged board with all the chips removed, maybe not even that much. I don't personally think the damage is that bad. Will the corrosion come back if you do a rookie repair? Solid maybe. Likely at some point. For me it would be worth $50 to tinker with it and hopefully have the satisfaction of fixing something, get your feet wet with simple board repair, etc. If you decide to sell the game after you fix the board, I would definitely disclose that it had some battery damage at one point. Or sell it with the replacement and keep yours as a spare. My first major board repair was a badly damaged System 11 board. My soldering wasn't great, but I got it to work. This was probably close to 10 years ago and I bet it still works. Good luck!